Field of Invention
The present invention relates to an air conditioning system, and more particularly to a water-cooled split-type air conditioning system comprising a water cooling unit which utilizes water as a cooling agent.
Description of Related Arts
Referring to FIG. 1 to FIG. 3 of the drawings, a conventional air-cooled split air conditioning system is illustrated. The air-cooled split air conditioning system comprises an outdoor unit 100P and two indoor units 200P. The outdoor unit 100P usually comprises a compressor 101P, a power device 105P, a heat exchanging coil 102P, and an air cooling unit 103P accommodated in a housing 104P. The housing 104P has a refrigerant inlet 1041P and a refrigerant outlet 1042P. Refrigerant in vaporous or steam state is pumped into the heat exchanging coil 102P through the refrigerant inlet 1041P. The air cooling unit 103P which is usually embodied as a fan draws ambient air into the housing 104P. The ambient air drawn into the housing 104P is arranged to perform heat exchange with the refrigerant in the heat exchanging coil 102P and extract heat from the refrigerant. The air having absorbed heat from the refrigerant is then expelled out of the housing 104P. At the same time, the refrigerant converts into liquid state and is arranged to leave the outdoor unit 100P through the refrigerant outlet 1042P. The outdoor unit 100P and the indoor unit 200P are connected by a first and a second refrigerant hose 300P.
The refrigerant coming from the outdoor unit 100P is guided to flow, usually through a dryer filter 301P and an expansion valve 400P, into an evaporator unit 201P located in each of the indoor units 200P. The refrigerant absorbs heat from the space in which the corresponding indoor unit 200P is located (referred to as indoor space hereinafter).
Referring to FIG. 4 to FIG. 6 of the drawings, a conventional air-cooled split heat pump system is illustrated. The conventional air-cooled split heat pump system is structurally similar to the above-mentioned air-cooled split air conditioning system except that the conventional air-cooled split heat pump system further comprises a four-way valve 5012P provided in the outdoor unit. Thus, the conventional air-cooled split heat pump system comprises an outdoor unit 501P, and two indoor units 502P. The outdoor unit 501P comprises an outdoor housing 5014P, a compressor unit 5011P, a four-way valve 5012P, an outdoor heat exchanging unit 5013P, an air cooling unit 5015P, and a power device 5016P. The indoor unit 502P comprises an indoor heat exchanging unit 5021P, a plurality of filters 5022P, a plurality of expansion valves 5023P, and a plurality of unidirectional valves 5024P.
The conventional air-cooled split heat pump system may be selectively used as an air conditioner for producing cool air within the indoor space. Alternatively, it may act as a heat pump for delivering heated air in that predetermined indoor space.
Referring to FIG. 6 of the drawings, it illustrates a refrigerant cycle of the conventional air-cooled split heat pump system. The four-way valve 5012P has first through fourth connecting ports 1P, 2P, 3P, 4P. When the conventional air-cooled split heat pump system acts as an air conditioner, the first connecting port 1P of the four-way valve 5012P is connected to the compressor unit 5011P and the second connecting port 2P which is connected to the outdoor heat exchanging unit 5013P. The third connecting port 3P of the four way valve 5012P is connected to the fourth connecting port 4P, which is connected to the indoor heat exchanging unit 5021P. The refrigerant sequentially flows through the compressor unit 5011P, the first connecting port 1P, the second connecting port 2P, the outdoor heat exchanging unit 5013P, the unidirectional valve 5024P, the filter 5022P, the expansion valve 5023P, the indoor heat exchanging unit 5021P, and finally back to the compressor unit 5011P.
When the conventional air-cooled split heat pump system acts as a heat pump, the first connecting port 1P is connected to the compressor unit 5011P and the fourth connecting 4P, which is connected to the indoor heat exchanging unit 5021P. On the other hand, the second connecting port 2P, which is connected to the outdoor heat exchanging unit 5013P, is connected to the third connecting port 3P which is connected to the compressor unit 5011P. The refrigerant sequentially flows through the compressor unit 5011P, the first connecting port 1P, the fourth connecting port 4P, the indoor heat exchanging unit 5021P, the one-way valve 5024P, the filter 5022P, the expansion valve 5023P, the outdoor heat exchanging unit 5013P, and finally back to the compressor unit 5011P.
The above-mentioned air-cooled split air conditioning system and air-cooled split heat pump system have a common disadvantage of having a relatively low coefficient of performance (C.O.P) which is the efficiency ratio of the amount of heating or cooling provided by the respective heating or cooling unit. For the above mentioned systems, the C.O.P is approximately 3.2. This is unsatisfactory in view of rapidly increasing energy demand throughout the world.